SANTA CLARA, CA - The fact that the only question about the San Francisco 49ers offense heading into a rematch against the New York Giants is Alex Smith's sprained middle finger illustrates just how much has changed since the NFC championship game.

Smith has become that important to San Francisco's success.

Jim Harbaugh heralded his quarterback Monday, a day after the defense heavy 49ers (4-1) whipped the Buffalo Bills 45-3 by gaining a franchise-record 621 yards. Harbaugh said Smith "just is a better player" than the former quarterback ever was and has helped the 49ers evolve into one of the NFL's most creative units.

When the Giants (3-2) return to Candlestick Park on Sunday, they might not recognize the 49ers offense. As Harbaugh said, "the talent level has been upgraded."